Grounding fitting



March 22, 1938. e. c. THOMAS. JR 2,

GROUNDING FITTING Filed Sept. 24, 1955 2 Sheets-Sheet l INVENTOR GEORGEC; THOMAS JR.

Match 8- G. c. THOMAS, JR

GROUNDING FITTING' Filed Sept. 24, 1935 2 Sheets'Sheet 2 w o h EOEINVENTOR GEORGE G.

yMAS JR ATTORNEYS Patented Mar. 22, 1938 UNITED" STATES 2,112,058GBOUNDING FITTING George C. Thomas, Jr., Westiield, N. 1., assignor to'The Thomas & Betta-Cm, Elizabeth, N. 1., a corporation of New JerseyApplication September 24, 1935, Serial No. 41,847

' 1 Claims. -(Cl. 173-273) The invention relates to a grounding fittingby means of which a wire which is connected with electrical apparatusmay be grounded tov a me. tallic conductor, such as a water pipe,grounding 5 rod, many other means which is provided for establishingelectrical connection with the ground. The invention relatesparticularly to a grounding fitting in which the wire to be groundedserves as its own hinge pin for the clamping members which grip thegrounded electrical conductor. Be-

cause of the fact that the wire to be grounded serves as a hinge-pin, itis firmly pressed into contact with the two clamping members of thegrounding fitting and thereby establishes a good 5. electrical contactwith both members. Other elements of the invention will be more apparentV a grounded electrical conductor therebetween.

The user may select one of a plurality of positions relatively to a.clamping seat upon a clamping member and thereby adapt the fitting fordifferent sizes of conductors or pipes.

0' Another object of the invention is to construct a grounding fittingin which the wire to be grounded serves as its own hinge pin between thetwo clamping members forming part of the grounding fitting and in whichat least one of the clamping members is provided with a pinrality ofhinge bearings so that the one grounding fitting is adapted to clampvarious sizes of pipes, rods, and other grounded electrical conductorsmerely by selecting the hinge bearing best e suited for the size ofgrounded conductor to'which the fitting is to be clamped.

Another object is to devise a reeniorcing memher for the wire to begrounded at the point where it serves as a hinge pin 1 or the twoclamping members of the. grounding fitting and which rceniorcing meansalso serves as a retaining means for holding the two clamping members ofthe grounding fitting together prior to the use of the grounding fittingin service.

A'still further object is to construct a grounding fitting in which thewire.to be grounded serves as its own hinge pin for the two clampingmembers and which fitting is provided with a bearing for the armorsurrounding the grounding wire so that the armor also establisheselectrical contact with the grounding fitting and is clamped I inposition in its bearing upon tightening oi the grounding fitting upon anelectrical conductor. It the wire is covered with insulation instead ofarmor, then the insulation is gripped in the bearing.

Another object of the invention is to devise a grounding fitting havingtwo clamping members, at least one of which carries a plurality of hingebearings for receiving, as a hinge pin, the wire 10 to be grounded sothat the grounding fitting is adapted for various sizes of electricalconductors, and to reeniorce the portion carrying the plurality of hingebearings, at the point where this portion joins the portion of theclamping member 15 having the clamping seat, with a rib which-extendslengthwise of the clamping member and serves also as a holding means forthe head of an operating bolt by which the clamping members are forcedtogether to grip the electrical conductor to which the wire is adaptedto be grounded. 20

A further object of the invention is to construct a grounding fittinghaving an insertable clamping seat by which the grounding fitting isadapted to clamp a smaller size of electrical conductor than 2 thatwhich the grounding fitting is capable of 5 receiving and clampingwithout the insertable clamping seat.

Other objects of the invention will be more apparent from the followingdescription taken in connection with the accompanying drawings showingthe preferred embodiments of the invention, in which:

V Figure 1 is an exploded view of the two clamping members of thegrounding fitting preparatory to being assembled upon a groundedmetallic conductor which in the illustration is shown as a pipe.

Figure 2 is a side view of the grounding fitting assembled and grippingthe grounded pipe. The wire to be grounded is inserted in one of the 40plurality of hinge bearings provided so that it serves as a hinge pinfor the two clamping members.

Figure 3 is a top viewoi the grounding fitting, or as viewed from theleft-hand side of Figure 2 45 with a grounded pipe gripped therein andthe wire to be grounded serving as a hinge pin between the two clampingmembers.

Figure 4 is a'view from the other side of the grounding fitting shown inFigure 2, or from the 50 right-hand side of the latter view.

Figure 5 shows the grounding fitting with the wire to be groundedinserted in another of the hinge bearings so that the grounding fittingis adapted to grip a smaller diameter of grounded 55 conductor which isshown as being a smaller diameter of pipe than that shown in Figures 1through 4. I

Figure 6 shows a clamping seat which is insertable into position overthe clamping seat of one of the clamping members of the groundingfitting so that the grounding fitting is capable of gripping a smallerdiameter grounded conductor than that which the grounding fitting isotherwise adapted to receive and clamp.

Figure 7 is a front view of the insertable clamping seat of Figure 6.

Figure 8 is a view showing the back of the insertable clamping seat ofFigure 6.

Figure 9 is an assembly view of the grounding fitting with theinsertable clamping seat of Figure 6 in position in the groundingfitting and gripping a smaller diameter of grounded conductor.

Figure 10 is a cross section through the hinge bearings of the groundingfitting, taken on line Iii-l of Figure 9, and shows how the groundingwire is gripped in the hinge bearings in contact with both clampingmembers.

Figure 11 is a top view of the grounding fitting of Figure 9 showing themanner in which the insertable clamping seat is secured in position andalso showing a section through the hinge bearings with the groundingwire serving as the hinge pin and the grounding wire being strengthenedor stiffened by a reenforcing bushing.

Figure 12 is a front view of the reenforcing means or bushing which isinsertable over a smaller diameter wire and serves to reenforce the wireas a hinge pin and also serves to retain the two clamping, memberstogether in assembled relation when the grounding fitting is not in use.

Figure 13 is an end view of the reenforcing hinge bushing of Figure 12.

The grounding fitting of the invention provides a simple construction bymaking the grounding wire serve as its own hinge pin or fulcrum betweenthe two clamping members which grip the grounded electrical conductor towhich the wire is to be electrically connected. Grounding fittingsgenerally provide a separate means for securing the grounding wire tothe grounding fitting and such separate means is dispensed with in theconstruction herein. Again, the grounding wire in serving as the hingepin for the two clamping members of the grounding fitting alsoestablishes direct electrical contact with the two clamping parts of thefitting so that a better electrical ground is established. As a matterof fact, a double grounding path is provided through each clampingmember of the fitting. The grounding fitting of the invention also lendsitself easily and readily and with a minimum number of parts to gripgrounding conductors of many different sizes and shapes.

The grounding fitting includes two clamping members 20 and 2| which arehinged together with the grounding wire W serving as the hinge pin. Theclamping member 20 is provided with a clamping seat 22 formed by theangularly disposed faces which carry serrations 23 for biting into thesurface of the grounded conductor C, which is shown as a pipe in thisfigure. The serrations enable the pipe to be more firmly gripped and abetter electrical connection is established by the serrations diggingthrough any scale or dirt upon the surface of the conductor. A hingebearing 24, which is preferably a hole,- is disposed at one end of theclamping member 20. A wire covering bearing 25 in the form of a bushingis provided in substantial alignment with the hinge bearing 24 in orderto receive the armor or insulation covering with which the groundingwire may be covered. Many wires, however, are not covered. The wirecovering bearing 25 is provided with the clamping member which carriesthe single hinge bearing which is particularly the clamping member 20having the single hinge bearing 24-. The other end of the clampingmember 20 carries a recess 26, which is preferably a. hole, in order toreceive an operating means 21, such 'as the bolt shown in Figure 2.

The other clamping member 2| is also provided with a clamping seat 32which is again formed preferably by angularly disposed siu'faces. whichsurfaces carry serrations 33 identical with the serrations 23 carried bythe clamping member 20. The clamping member 21 carries at least oneextension 34 which preferably extends substantially at right angles tothe general plane of the clamping member. Two such extensions areillustrated spaced from each other and it is clear that only one or morethan two may be provided if desired. Each extension 34 is provided witha plurality of hinge bearings which are spaced from each other on theextension. The preferred form of each hinge bearing is again a hole,there being three holes 35, 36 and 31 provided in each extension 34. Thepurpose of these spaced hinge hearings will be discussed more fullyhereinafter. The other end of the clamping member 2| carries a recess38-, which is preferably a hole, to receive the operating means, such asthe bolt or screw 21 shown in Figure 2.

The clamping member 2i has a pair of reenforcing ridges 42, one of whichextends from or forms a continuation of and merges with each extension3d and then passes over the back of the clamping member 2! and widensout a spaced distance on either side of the hole 38 for the operatingmeans. These spaced flanges or ridges 42 are spaced apart a distance sothat the head 28 of the operating bolt 21 is received therein andretains the bolt against turning. Reenforcing ridges 43 are alsoprovided upon the back of the clamping member 2B, but they do notstraddle the hole 28.

The hinge bearing or hole 31 is adapted for clamping a one inch groundedpipe as shown in Figures 1 through 4. The hinge hearing or hole at isintended for three-quarter inch pipe, although a three-quarter inch pipeis shown in Figure as being gripped from the hinge hole 35. The hingehole 35 is intended for one-half inch pipe. It is evident that theplurality of hinge holes 35, 3E and 31 are adapted to clamp more thanone size of pipe so that the three hinge holes provide considerablelatitude in the sizes of pipes or rods to be received and clampedbetween the clamping seats 22 and 32.

The operating means for forcing the clamping members together to grip agrounded conductor preferably includes the bolt or screw 21 having asquare head 28, the fiat sides of which are received between the flanges42 and prevented from turning thereby. An operating nut 45 is receivedon the bolt or screw 21. This operating means is preferably carried uponthe grounding fitting and passes through the bolt holes 26 and 38 in theends of the respective clamping members 20 and 2|, as previouslydescribed. Any other operating means for forcing the clamping memberstogether to grip the grounded conductor is contemplated.

The operation of the grounding fitting will now be described. A groundwire to be electrb 'cally grounded to the metallic conductor is insertedthroughthe hinge bearing 24 on the clamping member 20 and through oneof-the hinge bearings 35, 36 or 31 on the clamping member 2|. Thisground wire forms a hinge pin between the two clamping members which arehingediy secured together thereupon. A metallic conductor, such as thepipe 0, is then positioned between the clamping seats 22 and 32, and theoperating bolt 21 is passed through the holes 26 and 38 whereupontightening of the'opnot essential for hinge bearings.

Some grounding wires, and particularly the smaller sizes of groundingwires. carry an insulation or particularly a spirally wound metallicarmor R as shown in Figure 10. A bushing or armor bearing 25 is providedhaving a bore 49 which is adapted to receive the armor R. Upontightening of the operating nut M5, the side of the bore 49 grips thearmor and establishes electrical connection therewith and also securesthe armor within the bushing or sleeve. The bushing 25 also provides acovering for the ragged end of the armor.

In order "to adapt the grounding fitting for even smaller diameters orsizes of pipes, rods or-other metallic conductors, an insertableclamping seat Ellis provided as illustrated in Figures 6, 7 and 8. Thisinsertable c'lampin-gseat has angularly disposed clamping surfaceshaving serrations 52 for biting into the pipe or rod. This clamping seatW carries means for securing the seat in place'upon one of the clampingmembers. Any

desirable securing means may be utilized, that illustrated comprising apair of bendable tabs 53 projecting from the clamping seat, which tabsproject beyond the edge of the clamping member 2| so that the tabs maybe bent thereovenas illustrated in Figures and 11, to secure theinsertable clamping seat in position. The edges 5d of the insertableclamping seat 59 engage a serration 33 on each angular face of theclamping seat 32 and the clamping seat is retained in position againstshifting by the serrations. Also the sides 55 01 the insertable clampingseat 50 engage the sides of the clamping member 2| and the insertableclamping seat is additionally supported in position by this engagement.A half inch rod is shown in Figure 9 as being clamped within thegrounding fitting utilizing .the insertable clamping seat 50. It isclear that by properly proportioning the insertable clamping seat,smaller diameters of pipes or rods as well as various shapes of pipesand rods may be clamped within the grounding fitting. It is clear alsothat, if desired, an insertable clamping seat may be used for each ofthe clamping members 20 and 2!,

If the grounding wire W to be clamped within the hinge bearings Hand 35,36 or 31 is relatively small, there is some possibility that such smallwire may be sheared off if the operating nut 45 is securely tightened.In order to avoid forcing means and the wire are this possibility, areenforcingmeans 58 is. provided which is also projected through thehinge bearings with thegrounding wire. As illustrated in Figures 12 and13, this reeniorcing means is preferably tubular or a bushing andcollapsible so that under pressure in the hinge bearings, thebushingcontracts or collapses and the grounding wire W is securelyanchored within the bushing and the latter and wire are both firmlyclamped in the hinge bearings. Good electrical contact is thereforeestablished between the wire W and the clamping members 20 and 2!.

, The collapsible reenforcing means 58, particu; larly illustrated, istubular and is rendered contractile by a slot or particularly by rollinga fiat plate circularly so that the ends thereof overlap.

' With this. type or collapsible reenforclng means, there isnosubstantial deformation of the reenforcing means, other thancircularly, so that the reenforcing means 58 substantially engages theentire circumference of the grounding wire W.'

'I'his'reenforcing means is shown in position in Figures 10 and 11 andunder the clamping action of the operating means 21, 45, both thereengripped within the hinge bearings.

The reenforcing means 58, in addition to reenforcing a, smaller diametergrounding wire W, also serves to retain the hinge portions of theclamping members and 2! in hinged relation when in transit or boxed orat any time when the grounding fitting is not in use. The reenforcingmember is merely inserted in the hinge bearing it and any one of thehinge bearings 35, 36 or 31 upon the clamping member 2! and this retainsthe hinge portions of the two clamping members together. Any other typeof reenforcing means is contemplated, as well as any other means whichis insertable within the hinge bearings in order to retain the hingeportions of the two clamping members 20 andll in assembled relation.

The invention has been illustrated as having two clampingmembers 20 and21 one of which, namely 20, is provided with a single hinge bearing 24and the other 2| is provided with a plurality of hinge bearings 35, 36and 31. It is to be understood that each clamping membermay I beprovided with a plurality of hinge bearings and this form iscontemplated herein. Again, inthe form particularly illustrated, therelation of clamping seat, hinge and operating means is that of a leverof the second class. It is within the provinceof the invention toposition these parts with respect to each other so as to havea relationof levers of the first and third class.

Various modifications will occur to those skilled in the art in theconfiguration, composition and disposition of the component elementsgoing to make up the invention as a whole, as Well as in to receive awire to be grounded and the others of which receive the ground wire forconductors of different sizes, at least one hinge bearing upon anotherclamping member to also receive the grounding wire which wire serves asa hinge pin between the clamping members, clamping seats upon theclamping members between which a metallic conductor is adapted to beclamped, and operating means to force the clamping members together togrip the metallic conductor between the clamping seats and grip thegrounding wire against the hinge bearings in which the grounding wire isreceived.

2. A grounding fitting for a grounding wire comprising clamping memberseach having a hinge bearing'to receive a wire to be grounded which wireserves as a pin to hingedly secure the clamping members together,clamping seats upon the clamping members between which a metallicconductor is adapted to be clamped, operating means to force theclamping members together to grip a metallic conductor between theclamping seats and grip the grounding wire against the hinge bearing,and a. reeniorcing means adapted to be placed in contact with the wireand inserted in the hinge hearings to reenforce the wire and to retainthe hinge bearings together.

3. A grounding fitting for a grounding wire comprising clamping memberseach having a hinge bearing to receive a wire to be grounded which wireserves as a pin to hingedly secure the clamping members together,clamping seats upon the clamping members between which a metallicconductor is adapted to be clamped, operating means to force theclamping members together to grip a metallic conductor between the seatsand grip the grounding wire against the hinge bearings, and acontractile tubular reenforcing means received in the hinge bearings andadapted to receive the grounding wire therein to reenforce the wire andalso to retain the clamping members together when not in use.

4. A grounding fitting for a grounding wire comprising clamping memberseach having a hinge bearing to receive a wire to be grounded which wireserves as a pin to hingedly secure the clamping members together, areceiving bearing for a wire cover carried by one of the clampingmembers and located in substantial alignment with the hinge bearing,clamping seats upon the clamping members between which a. metallicconductor is adapted to be clamped, and operating means toiorce theclamping members together to grip a metallic conductor between theseats, the grounding wire against the hinge bearing and the wirecovering in the cover receiving bearing.

5. A grounding fitting for a grounding wire comprising clamping members,extension means carried by one clamping member and extendingsubstantially at right angles to the general plane thereof, a pluralityof spaced hinge holes in the extension means, a hinge hole in the otherclamping member which hinge hole and one of those in the extension meansare adapted to receive a wire to be grounded which wire serves as ahinge pin between the two clamping members, clamping seats upon theclamping members between which a metallic conductor is adapted to beclamped, and operating means to force the clamping members together togrip a metallic conductor between the clamping seats and grip thegrounding wire against the sides of the hinge holes.

6. A grounding fitting for a groundingwire comprising clamping members,extension means carried by one clamping member and extendingsubstantially at right angles to the general plane thereof, a pluralityof spaced hinge holes in the extension means, a hinge hole in the otherclamping member which hinge hole and one of those in the extension meansare adapted to receive a wire to be grounded which wire serves as ahinge pin between the clamping members, clamping seats upon the clampingmembers between which a metallic conductor is adapted to be clamped,reenforcing flange means extending from the extension means as acontinuation thereof over the back of the clamping member, and operatingmeans to force the clamping members together to grip a metallicconductor between the clamping seats and grip the grounding wire againstthe sides 0! the hinge holes.

7. A grounding fitting for a grounding wire comprising clamping members,extension means carried by one clamping member and extendingsubstantially'at right angles to the general plane thereof, a pluralityof spaced hinge holes in the extension means, a hinge hole in the otherclamp ing member which hinge hole and one of those in the extensionmeans are adapted to receive a wire to be grounded which wire serves asa hinge pin between the clamping members, clamping seats upon theclamping members between which a metallic conductor is adapted to beclamped,

openings at the end of each clamping member, a pair of flanges extendingfrom the extension means over the back of the clamping member and oneflange passing on each side of the opening upon one clamping member, anoperating bolt passing through the openings to force the clampingmembers together to grip a metallic conductor between the clamping seatsand grip the grounding wireagainst the sides of the hinge holes, and ahead on the operating bolt received between the flanges to prevent theoperating bolt from turning.

8. A grounding fitting for a grounding wire comprising clamping members,a hinge bearing in each clamping member which hinge bearings are adaptedto receive a wire to be grounded which wire serves as a pin to hingedlysecure the clamping members together, clamping seats upon the clampingmembers between which a metallic conductor is adapted to be:clamped,openings at the end of each clamping member, a pair of flanges extendingover the back of one of the clamping members and one flange passing oneach side of the opening in the end of the clamping member, an operatingbolt passing through the openings to force the clamping members togetherto grip a metallic conductor between the clamping seats and grip thegrounding wire against the sides of the hinge holes, and a head on theoperating bolt received between the flanges to prevent the operatingbolt from turning.

9. A grounding fitting for a grounding wire comprising clamping members,a hinge bearing in each clamping member which hinge bearings are adaptedto receive a wire to be grounded which wire serves as a pin to hingedlysecure the clamping members together, clamping seats upon the clampingmembers between which a metallic conductor is adapted to be clamped, aninsertable clamping seat received over the clamping seat carried by oneof the clamping members, and operating means to force the clampingmembers together to grip a metallic conductor between the clamping seatsand grip the grounding wire against the hinge bearings.

10. A grounding-fitting for a grounding wire comprising'clampingmembers, a hinge bearing in each clamping member which hinge bearingsare adapted to receive a wire to be grounded:

which wire serves as a pin to hingedly secure the two clamping memberstogether, clamping seats upon the clamping members formed with angularlydisposed surfaces between which seats a metallic conductor is adapted tobe clamped, serrations upon the clamping seats, an insertable clampingseat received over the clamping seat carried by one of the clampingmembers and the edges thereof engaging the serrations upon the clampingseat to retain the insertable seat in position, and-operating means toforce the clampcomprising two clamping members; a hinge bear ing in eachclamplngmember which hinge bearings are adapted to receive a wire to begrounded which wire serves as a pin to hingedly secure the twoclampingmembers together, clamping seats upon the clamping members between whicha metallic conductor is adapted to be clamped, serrations upon at leastone seat, an insertable clamping seat received over the clamping seatcarried by one of the clamping members, edges carried by the insertableseat engaging in the i serrations, tabs carried by the insertable'clamping seat and bendable over the edge of the clamping member, theserrations and tabsanchoring the insertable clamping seat upon theclamping member, and operating means to force the clamping memberstogether to grip a metallic conductor between the clamping seats andgrip the grounding wire against the hinge bearings.

GEORGE c. moms, JR.

